Isolation and Screening of Zinc Solubilizing Microbes: As Essential Micronutrient Bio-Inputs for Crops

Abstract

Zinc is indispensable micronutrient for optimum plant growth. Soil is a rich source of zinc but major portion of it is in the form of insoluble complexes and therefore is inaccessible to plants. This inorganic zinc can be converted to soluble form (divalent cation) with the help of zinc solubilizing microbes. Microbes solubilize zinc through different mechanisms including acidification, oxidoreductive reactions, or production of siderophores. Based on zinc solubilization property, microbes can be isolated from soil by the use of selective minimal media containing zinc. The zone of clearance formed because of zinc solubilization can confirm the presence of zinc solubilizing microbe. Finally, the quantification of solubilized zinc can be made by atomic absorption spectroscopy.

Innovations in Agricultural Bio-Inputs: Commercial Products Developed in Argentina and Brazil

“…Consequently, we do not have new generations of bio-inputs replacing the old generations as if in a technological continuum of new technologies taking the place of the old ones, but we rather have parallel races for the improvement of existing products and the development of new products for different markets happening at the same time. The value for money and the efficacy in different field situations of these innovations in bio-inputs [6,12,15] will define the products that may remain on the market over time. Since any technological development and its adoption can be associated with potential risks, especially when living microorganisms are released into the environment, corporate accountability and continued academic research are fundamental for this sector in the long term.…”

“…Innovations range from improving the efficacy of existing bio-inputs such as inoculants, bio-fertilizers, and bio-pesticides [6][7][8][9] to developing new products based on modern technologies such as nanotechnology and molecular biology [10,11]. There are also efforts to combine different microorganisms into single products [12][13][14] that solubilize nutrients available in the soil and help plants resist pests and drought [15,16]. Industrial…”